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Title 21

Displaying title 21, up to date as of 7/15/2026. Title 21 was last amended 7/09/2026.
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Title 21Food and DrugsPart / Section
Chapter IFood and Drug Administration, Department of Health and Human Services1 – 1299
Subchapter EAnimal Drugs, Feeds, and Related Products500 – 599
Part 500General500.23 – 500.1410
Subpart A [Reserved]
Subpart BSpecific Administrative Rulings and Decisions500.23 – 500.50
Subpart CAnimal Drug Labeling Requirements500.51 – 500.55
§ 500.51Labeling of animal drugs; misbranding.
§ 500.52Use of terms such as “tonic”, “tone”, “toner”, or “conditioner” in the labeling of preparations intended for use in or on animals.
§ 500.55Exemption from certain drug-labeling requirements.
Subpart DRequirements for Specific Animal Drugs500.65
§ 500.65Epinephrine injection 1:1,000 in 10-milliliter containers for emergency treatment of anaphylactoid shock in cattle, horses, sheep, and swine.
Subpart ERegulation of Carcinogenic Compounds Used in Food-Producing Animals500.80 – 500.92
§ 500.80Scope of this subpart.
§ 500.82Definitions.
§ 500.84Conditions for approval of the sponsored compound.
§ 500.86Marker residue and target tissue.
§ 500.88Regulatory method.
§ 500.90Waiver of requirements.
§ 500.92Implementation.
Subpart FMethods for Detection of Residues of Carcinogenic Compounds Used in Food-Producing Animals500.1410
§ 500.1410N-methyl-2-pyrrolidone.